That should be very good news for pilots and mechanics. Much better to work in a field with a shortage of qualified people than in a field with a surplus of workers. Supply and demand can be a good thing.
As to pilots, there may be an industry-wide shortage of pilots in coming years but I expect that UA, DL, AA and WN won't have any trouble filling openings for many years as they attract applicants from the low-paying regionals. The low-paying regionals, of course, may have significant difficulties down the road, as they don't offer max rates of $200+/hr plus all the "glamour" of flying long-haul international routes (applicable to UA, DL and AA but not applicable to WN, of course).
Mechanics? Same story, really. Lower-paid MRO employees will gravitate towards the UA, DL, AA and WN to seek higher wages. Dunno how those lower-paying employers will replace the lost employees unless mechanics lobby for changes in law that require heavy maintenance to occur in the USA.
Line maintenance is where mechanics will be paid bigger bucks than the "can be done anywhere" heavy overhaul. Just like in other fields (nursing), higher wages will eventually attract more workers to become trained and qualified. Once the majors are all paying $50/hr or more for line mechanics (as UPS already is), the remaining schools will fill with applicants.